OXIDATION INCIDENTS

Many of the inorganic (mineral) acids have been involved in various incidents, either as catalysts or reactants, the most common, so far as frequency is concerned, being nitric acid in oxidation incidents. Individual acids are ... 

OXIDATION INCIDENTS, PEROXIDATION INCIDENTS, PLANT CLEANING INCIDENTS... 

Such unspecific oxidative attack is also discussed as a possible route in the biodegradation fate of PVA. Oxidation of PVA should be possible, as very aggressive oxidative species can be generated by the extracellular enzyme mixtures of wood-rotting fungi. Unspecific oxidative incidents are to be expected when strongly oxidising low molecular mediators react with PVA, a mechanism that is described as the indirect action of laccase enzymes [77]. Reports about the beneficial... 

NITRATION INCIDENTS OXIDATION INCIDENTS PEROXIDATION INCIDENTS PLANT CLEANING INCIDENTS POLYCONDENSATION REACTION INCIDENTS POLYMERISATION INCIDENTS REDOX REACTIONS SULFONATION INCIDENTS... 

Oxidants, 295 Oxidants as herbicides, 300 Oxidation incidents, 300 Oxidation processes, 300 N-Oxides, 300 Oxides of nitrogen, 301 Oxime carbamates, 302 Oximes, 302 Oxiranes, 303... 

Various series of experiments were carried out on different types of samples. All samples consisted of three layers, the Ni-YSZ substrate, Ni-YSZ anode and YSZ electrolyte. The substrates were prepared by the Coat-Mix process and warm pressing. The chemical composition is 56 wt.% NiO and 44 wt.% YSZ for both the Coat-Mix substrate and the anode. Characterization of the Ni-YSZ-cermets with respect to redox tolerance was performed at free standing samples with dimensions 50x25 mm and a thickness of 1.5. 1.0 or 0.5 mm to investigate the influence of the re-oxidation temperature, time of re-oxidation, incident air flow, substrate thickness and substrate porosity on the mechanical integrity of the substrate and other cell components. Examples of the free standing samples that were used for the tests are shown in Fig. 1. 

Maturation is conducted in closed, full containers to prevent oxidation and aerobic growth of microorganisms. Etee air contact with low alcohol wine soon leads to vinegar. Except for those sherry types already mentioned, wines ate exposed to air minimally and temporarily. During transfers incident to bulk storage and processing, some air exposure is almost inevitable, mote in total the longer the wine is held. In the cases of white and pink table wines, it is ordinarily as neat zero as possible, and stainless steel or other impermeable containers, inert gas headspace, etc ate employed. Red wines withstand and even benefit from small but repeated exposures to air. 

Vitamin E can also act as an antioxidant (qv) in animals and humans alone or in combination with vitamin C (qv). Both are good free-radical scavengers with the vitamin C acting to preserve the levels of vitamin E (35). Vitamin E in turn can preserve the levels of vitamin A in animals (13). It has been shown that vitamin E reduces the incidence of cardiovascular disease (36—39). This most likely results from the antioxidant property of the vitamin which inhibits the oxidation of low density Hpoproteins (LDLs) (40—42). The formation of the oxidized LDLs is considered important in decreasing the incidence of cardiovascular disease (43). 

Process Safety Considerations. Unit optimization studies combined with dynamic simulations of the process may identify operating conditions that are unsafe regarding fire safety, equipment damage potential, and operating sensitivity. Several instances of fires and deflagrations in ethylene oxide production units have been reported in the past (160). These incidents have occurred in both the reaction cycle and ethylene oxide refining areas. Therefore, ethylene oxide units should always be designed to prevent the formation of explosive gas mixtures. 

Ethylene oxide has been shown to produce mutagenic and cytogenic effects in a variety of test systems (226). An increased frequency of chromosomal aberrations in peripheral lymphocytes of monkey exposed to ethylene oxide for 104 weeks has been reported (240). In mice, it is an effective inducer of chromosome breaks leading to dominant-lethal mutations. In addition, ethylene oxide has been shown to induce heritable effects in the heritable translocation test conducted in mice exposed to ethylene oxide by inhalation (241,242). In this study, male mice were exposed to ethylene oxide ranging from 165 to 300 ppm for 6 h per day 5 or 7 days/week for 8.5 weeks. Ethylene oxide has also been shown to bind to proteins (243) as well as to DNA (244). Several studies on ethylene oxide-exposed workers have demonstrated an increased incidence of chromosomal aberrations and sister chromatid exchanges the relevance of such effects to human health evaluation is currendy uncertain. 

In an animal study of rats exposed by inhalation to ethylene oxide at 10, 33, or 100 ppm for approximately two years (245), and in a separate chronic rat study in which rats were exposed to 50 or 100 ppm of ethylene oxide (240), increased incidences of mononuclear cell leukemia, peritoneal mesothelioma, and various brain tumors have been reported. In an NTP (246) two-year inhalation study of mice at 50 and 100 ppm, alveolar/bronchiolar carcinomas and adenomas, papillary cystadenomas of the harderian gland, and malignant lymphomas, uterine adenocarcinomas, and mammary gland tumors were increased in one or both exposure groups. 

M. F. Toney and S. Brennan. Structural Depth Profiling of Iron Oxide Thin Films using Grazing Incidence Asymmetric Bra X-ray DiflFraction. J. Appl. Phys. 65J 4763, 1989. 

The UK Environment Agency deals with over 6000 oil pollution incidents each year. One estimate suggests tliat tlie cheiTtical industry contributes to 50% of all ah pollution witli proportions approximating to sulphur dioxide (36%), carbon dioxide (28%), nitrogen oxides (18%), carbon monoxide (14%) and black smoke (10%). Motor spirit refining is responsible for ca 26% of emissions of volatile organic compounds to the atmosphere. In 1996 there were over 20 000 reports of water pollution incidents with 155 successful prosecutions. 

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